Process of and apparatus for making concrete slabs



G. ATTERBURY.

PROCESS OF AND APPARATUS FOR MAKING CONCRETE SLABS.

APPLICATION mm MAR.15. 1919.

11,326,902, Patented Jan. 6, 1920.

UNITED STATES PATENT OFFICE.

GROS'VENOB ATTERBURY, OF NEW YORK, N. Y.

PROCESS OF AND APPARATUS FOR MAKING- CONCRETE SLABS.

Application filed March 15, 1919.

To all whom it may concern:

Be it known that I, GnosvENoR Arran- BURY, a citizen of the UnitedStates, residing in the city, county, and State of New York, haveinvented certain new and useful Improvements in Processes of andApparatus for Making Concrete Slabs, of which the following is adescription.

My invention relates to the art of making large slabs or blocks ofconcrete and the like. In casting such large blocks or slabs to be usedin walls and for similar purposes certain difiiculties have beenencountered which unduly enhance the cost of the product. Consequentlysuch separately cast large slabs or blocks have not come into use asbuilding material to any extent, although they have attractivepossibilities.

One of the diiiiculties referred to above is that the fluid mass ofconcrete or similar material has so large an hydrostatic pressure perunit volume that the resulting pressures on the retaining surfaces arevery high when casting a block of considerable size, and consequentlythe apparatus must be Very stiff in order to withstand such pressureswithout deformation. Since a building block must necessarily have truefaces, the apparatus heretofore used has been very expensive withresulting high unit costs of product. Moreover, there has been thedrawback in operating the previous apparatus that it was necessary to gointo the mold space to clean and oil the surfaces before every castingoperation, requiring that the apparatus be opened widely with aconsequent expenditure of floor space which is not economical.

Having in mind the foregoing difficulties, the principal object of myinvention is to provide a method of casting large blocks of concrete orsimilar material which shall permit the use of relatively inexpensiveapparatus.

A second object of my invention is to provide a relatively inexpensiveapparatus for casting large monolithic blocks or slabs, and one whichshall economize space in proportion to the output.

A further object of my invention resides in the particular arrangementand combination'of parts hereinafter described.

In the drawing,

Figure 1 is a plan view of an apparatus Specification of Letters Patent.

Patented Jan. 6, 1920.

Serial No. seams.

for practising my improved process and embodying my improvements incasting apparatus.

Fig. 2 is an elevational view of the apparatus shown in Fig. 1, partsbeing removed and parts being shown in section for purposes ofillustration.

Fig. 3 is a partial view in horizontal section illustrating theconstruction of two of the diaphragms or jackets shown in Fig. 1.

Fig. 4 is a detail view in perspective showing a portion of one end of amold space with the end member and diaphragms associated with saidspace, and also one of the diaphragms associated with an adjacent space.

In its general organization, the apparatus herein described is similarto that shown in my prior Patent Number 1,241,487.

In the drawing, 1, 1, are side members, preferably of the sameconstruction as the side members described and claimed in my saidapplication, and of sufiicient stiffness to withstand the full pressureof the material on one side thereof.

The space between the members 1 1 is divided into a plurality of moldspaces, such as 2, by means of diaphragms or jackets, such as 3. Thesejackets or diaphragms are relatively thin or light as compared with themembers 1, and are of such thickness as to preserve a true surface whensupported on one side against the hydrostatic pressure of the material.As shown in Fig. 1, I prefer to arrange the jackets 3 in pairs, thejackets of each pair being one on each side of a given mold space. Thejackets next the sides or members 1 of course are supported against thehydrostatic pressure by said members, but the jacket of a pair which isnot in contact with the side members is arranged to be supported by ajacket of another pair, the two being arranged back to back in contact,as best illustrated in Fig. 3, so that the hydrostatic pressures on thetwo adjacent and contacting jackets will balance when the fluid materialin the two adjacent mold spaces is brought to the same level. Thejackets 3 comprise face plates such as 3*, to the backs of which aresecured I-beams 4, the free faces of said beams being planed so that twojackets may support each other properly when placed back to back.Moreover, the free surfaces of the members 4 are lubricated so that theymay slide one on the other, for a purpose which will hereinafter appear.

The ends of the mold spaces 2 are closed by suitable end blocks such as5. The blocks 5 project laterally beyond the line of the ends of thejackets 3, and it will be seen to be necessary to retract both themembers 1, l and members 5, 5 from casting position in order to removethe casts. This is accomplished by curved spreader bars, such as 20,which coact with pins Q1 on the tops of the ends of the sides 1 andblocks 5, to spread apart the end pieces 5 at the same time the sides 1are separated to remove the casts. Any suitable means (not shown) may beused to separate the side members 1 farther than when in castingposition. One suitable mechanism for this purpose is shown in my priorPatent No. 1,241387.

Whenever desired, a single mold space, such as 2, may be divided intotwo or more parts by the use of supporter members such as that shown at6, or by compound supporters, such as illustrated at 7 In the process ofpouring the fluid material into the mold spaces, I maintain the level ofthe material approximately equal in all the mold spaces so that thehydrostatic pressures may be balanced on all the parts except the sidemembers and the end members. In this way the necessary strength of theparts is reduced to the minimum, the same being true also of the cost.

The lower ends of the jackets 3 have secured thereto angle irons such as8, which serve as shelves to support the weight of the block, such as 2when the same is being lifted. The space between the shelves 8 of agiven pair of jackets is closed at the bot tom by a chock block, such as9.

When it is desired to lift a block or slab, such as 2% from theapparatus, hooks may be engaged in holes, such as 10, (shown in Fig. i)at the ends of the jackets 3, and a pair of jackets with the inclosedblock conveniently lifted by a crane hoist secured to the hooks, thelubricated surfaces of the jackets facilitating the removal of the same.

I have designed my apparatus with a jacket on the face of each sidemember 1, since inthis way the side members do not need to be made withfacings, the jackets serving this purpose. I consider this to be bothmore economical in first cost and to facilitate the operation of theapparatus. However, 1 consider it within my invention to provide theside members with facings and to omit the jackets at these points.

It will be seen that I have illustrated an apparatus having a distancebetween sides 1 equal only to two mold spaces and the associated,jackets, but it will be understood that my apparatus may be constructedof any desired dimensions and that my process is equally applicable inthe operation of apparatus of greater size than that herein shown.

It will be seen, moreover, that it is froi time to time desirable toapply moldings to the casting surfaces of the molds or boxes, so as toform corresponding molds in the castings. My new system of jackets makesit possible to do this quickly by substituting jackets having moldingsthereon for those with plane surfaces, and also makes it possible toeffect alterations in the jackets without putting the entire castingapparatus out of business for the time required.

Having thus described my invention, I claim:

1. A method of simultaneously casting a plurality of cementitious slabscomprising pouring, into mold spaces separated by pairs of jacketsbearing against one another, the cementitious material in such manner asto maintain the level of the material substantially the same in all saidspaces.

2. An apparatus for casting large slabs of cementitious material,comprising in combination a pair of side walls of sufiicient stiffnessto maintain a true surface under full pressure of the material on oneside thereof, and jackets arranged between said walls and dividing thespace therebetween into mold spaces, there being two jackets back toback between adjacent mold spaces, said jackets being only of suchstifiness as to preserve a true surface when the pressure of thematerial thereon is substantially balanced.

3. An apparatus for casting large slabs of cementitious materialcomprising in combination a pair of side walls, jackets dividing thespace between said walls into mold spaces, said ackets being arranged inpairs.

on opposite sides of a given mold space and the jackets between twoadjacent mold spaces being arranged back to back in contact and readilyslidable one on the other.

l. An apparatus for casting large slabs of cementitious materialcomprising in combination a pair of side walls, jackets dividing thespace between said walls into mold spaces, said jackets being arrangedin pairs on opposite sides of a givenmold space and the jackets betweentwo adjacent mold spaces being arranged back to back and readilyslidable one on the other, said jackets being only of such stiffness asto preserve a true surface when the pressure of the material thereon issubstantially balanced.

5. An apparatus for casting large slabs of cementitious materialcomprising in combination a pair of side walls, jackets dividing thespace between said walls into mold spaces, said jackets being arrangedin pairs on opposite sides of a given mold space and the jackets betweentwo adjacent mold spaces being arranged back to back in contact andreadily slidable one on the other, said jackets having supportingshelves or ledges secured near the lower edges thereof, whereby a pairof jackets and its associated slab can be lifted together.

6. A method of simultaneously casting a plurality of cementitious slabscomprising placing one of a pair of jackets on each side of each moldspace so that the two jackets between adjacent fnold spaces bear againsteach other, pouring the cementitious material into said mold spaces insuch manner as to maintain the level of the material substantially thesame in all said spaces,

allowing the material to set, and withdrawing each individual slab fromthe apparatus by applying a lifting force to the pair of jacketsassociated therewith.

7. A casting apparatus for-casting concrete slabs comprising, incombination, side walls and jackets arranged parallel to said .sidewalls and dividing the space therebetween into mold spaces, said jacketsbeing arranged in pairs on opposite sides of the mold spaces so thatjackets of adjacent pairs bear against each other.

GROSVENOR ATTERBURY.

